After a brief account of the general principles of the method, a description is given of some aspects of the problems which
have been investigated in detail: behaviour of targets under ion-bombardment, determination of oxygen, carbon and nitrogen
at the surface of metallic targets, and determination of carbon and nitrogen in tantalum layers metallized on glass.
Dans un programme de recherche visant à étudier les différentes méthodes de dosage de l'oxygène dans les métaux non ferreux,
nous avons été amenés à examiner l'influence de l'oxygène de surface sur la détermination de l'oxygène dans la masse. Cette
analyse de la surface a été réalisée en utilisant les réactions nucléaires induites par des particules chargées de faible
énergie obtenues à l'aide d'un accélérateur Van de Graaff de 2 Mev.
Authors:G. Weber, D. David, L. Quaglia, J. Pauwels, and J. Vanaudenhove
Surface treatment on non-ferrous metals are proposed in order to minimize or determine quantitatively the interference of
gaseous contamination. These proposals result from a large number of determinations of superficial contamination on several
materials using microanalysis by nuclear reactions. This work is included in a larger program which aims the certification
of standard materials in their oxygen, nitrogen and carbon contents.
Authors:J. Barrandon, L. Quaglia, J. Debrun, M. Cuypers, and G. Robaye
The oxygen and carbon concentrations on metal surfaces were determined by two methods. The first method was based on the detection
of the emitted particles in the12C(d,p)13C and16O(d, p)17O reactions, the second one on the measurement of the induced radioactivities in the12C(d,n)13N and16O(t,n)18F reactions, respectively. The results, obtained by the two different methods for high purity metals, were in agreement. A
type of error which exists in the determination of trace amounts of carbon and oxygen in pure metals by combustion and reductive
fusion was quantitatively demonstrated. This error exists also in the determination of oxygen by 14 MeV neutron bombardment.
Authors:G. Del Fioe, J. Peters, L. Quaglia, J. Piette, R. Cantineau, C. De Landsheere, D. Raets, and P. Rigo
The synthesis of11C-acetate has been achieved via carbonation of methyl magnesium bromide with11C-labelled carbon dioxide. Using this procedure, 7.4 GBq /200 mCi/ of11CO2 produced by the14N/P,/11C nuclear reaction, was converted, within 20 min into11C-acetate with an activity higher than 2.22 GBq /60 mCi/. Chemical and biologic quality control shows that the product is pure, sterile, and pyrogen-free and therefore suitable for human use. Handling considerable amounts of activity has led us to automate the11C-acetate synthesis. The different parts of the system-programmable controller, sensors, automatic neutralization system-are described in detail.
Authors:G. Del Fiore, J. Peters, L. Quaglia, F. Boudjelida, M. Pardon, J. Piette, R. Cantineau, Ch. De Landsheere, and P. Rigo
An automated continuous flow process has been developed for the synthesis of11C-ethanol and11C-butanol. These alcohols were synthesized via the same route. The reaction of11CO2 with methylmagnesium bromide or with n-propylmagnesium chloride, followed by a lithium aluminum hydride reduction and hydrolysis produced respectively11C-ethanol and11C-butanol. Preparation can be completed in 25 min. In each case the radiochemical purity, as determined by high pressure liquid chromatography /HPLC/ was greater than 98%. Biological quality control shows that the products are suitable for human use. The process has been completely automated to limit radiation exposure to personnel, reduce preparation time, and increase reproducibility.